Mirror Tunnel Optical System for Extended Depth of Focus
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional OCT systems face a trade-off between lateral resolution and depth of focus, limiting their ability to achieve high-resolution imaging over long axial fields, particularly in applications like in-vivo cardiology and gastrointestinal tract imaging where extended depth of focus is required.
Innovation Solution
The introduction of a mirror tunnel based focusing optical system that generates multiple on-axis foci, extending the depth of focus by dividing the wavefront into multiple annular zones and using a cylindrical waveguide to transmit light of different propagation modes, allowing for a more than 10-fold improvement in resolution while maintaining similar depth of focus as conventional systems.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the numerical aperture of the objective is increased to improve lateral resolution, then the lateral resolution is improved, but the depth of focus is reduced
Solution Approach 1:
The wavefront is divided into multiple annular zones using a phase mask, creating multiple propagation modes that focus at different depths. This segmentation allows the system to maintain high lateral resolution while extending the depth of focus by combining multiple focal regions
Solution Approach 2:
The invention transitions from a single Gaussian beam focus to multiple foci arranged axially by introducing a phase mask that creates annular zones. This adds the dimension of axial distribution to the focal points, enabling extended depth of focus while maintaining lateral resolution
2Measurement precision
If conventional Gaussian beam optics is used to achieve high lateral resolution, then lateral resolution is improved, but the depth of focus is limited to a short range
Solution Approach 1:
The phase mask modifies the amplitude and phase parameters of the Gaussian beam by creating annular zones with specific transmission characteristics. This parameter change transforms the single-focus Gaussian beam into a multi-focus beam pattern with extended axial range
3Length of stationary object
If aperture apodization or synthesized aperture techniques are applied to increase depth of focus, then depth of focus is improved, but implementation complexity increases and performance is limited
Solution Approach 1:
The invention uses a simple phase mask with annular zones that can be easily fabricated and integrated into the optical system. This simple component replaces complex adaptive optics systems or multiple scanning mechanisms, achieving extended depth of focus with minimal added complexity
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach enables high-resolution, cellular-level imaging with a depth of focus exceeding 1.5 mm, suitable for in-vivo cardiology and GI tract imaging, and can be adapted for various imaging techniques, including spectral-domain and swept-source OCT systems.
Implementation Method 1
using a cylindrical waveguide to transmit light of different propagation modes
Implementation Method 2
a mirror tunnel based focusing optical system that generates multiple on-axis foci, extending the depth of focus by dividing the wavefront into multiple annular zones
Implementation Method 3
generates multiple on-axis foci, extending the depth of focus by dividing the wavefront into multiple annular zones
Data Source
AI summary
Exemplary apparatus and method are provided for illuminating a sample. With such exemplary apparatus and/or method, it is possible to, using at least one source arrangement, provide at least one first electro-magnetic radiation. Using an optical system of an optics arrangement, it is possible to receive the first electro-magnetic radiation(s), and modifying the at least one first electro-magnetic radiation to be at least one second electro-magnetic radiation so as to be forwarded to the sample. Further, with the optical system, it is possible to extend the at least one second electro-magnetic radiation into or across the sample for a distance of at least 2 times the Raleigh range of a Gaussian beam when the optics arrangement and the sample are stationary with respect to one another. Additionally, using the optical system, it is possible to control a placement of a focus of the at least one second electro-magnetic radiation on or in the sample.